The term 'PERIOD OF WATCHFULNESS' can be summarized as a VIGIL, which is a five-letter word. A VIGIL is an act of keeping watch or staying alert during a period of time, usually at night. It is often associated with religious ceremonies or other important events, such as funerals or memorial services. Vigils are also used to mark special occasions, such as anniversaries or birthdays. In some cases, vigils are held to protest or raise awareness about a particular issue.